Apparatus for detecting a substantially depleted or missing binder thread condition



Nov. 1, 1966 D. BARNETT ETAL 3,282,037

APPARATUS FOR DETECTING A SUBSTANTIALLY DEPLETED OR MISSING BINDER THREAD CONDITION 4 Sheets-Sheet 1 Filed April 15, 1963 m \mvem'oes E. DBAENETT W.-J.EEA

BY Moe? 190%.)

ATTOENEY Nov. 1, 1966 R. D. BARNETT ETAL 3,232,037

APPARATUS FDR DETECTING A SUBSTANTIALLY DEPLETED 0R MISSING BINDER THREAD CONDITION 4 Sheets-Sheet 2 Filed April 15, 1963 1956 R. D. BARNETT ETAL 3 282,037

9 APPARATUS FOR DETECTING A SUBSTANTIALLY DEPLETED OR MISSING BINDER THREAD CONDITION 4 Sheets-Sheet 5 Filed April 15. 1965 Nov. 1, 1966 R. D. BARNETT ETAL 3,282,037 APPARATUS FOR DETECTING A SUBSTANTIALLY DEPLETED I OH MISSING BINDER THREAD CONDITION Flled Apr-11 15, 1965 4 Sheets-Sheet 4 TO STEANDING CABLEE DEIVE MOTORS B\ND\NG A 4,

HEAD P MOTOR FEEQUENCY 'To 5a 69 [NEECT CURRENT VOLTAGE CONVERTER 76 4 lid 4 BRUSH AND 449 SUPR'ING A5 Assemaw (9 STRANDlNG CABLE? SUPPLY SDUECE United States Patent APPARATUS FQR DETECTING A SUBSTANTIALLY DEPLETED 0R MlSSlNG BINDER THREAD CON- DITION Richard D. Barnett, ()maha, andWilliam J. Rea, Ralston,

Nebn, assignors to Western Electric Company, incorporated, New York, N.Y., a corporation of New York Filed Apr. 15, 1963, Ser. No. 273,036 7 Claims. (Cl. 57-18) This invention relate to apparatus for detecting a substantially depleted or .missing binder thread condition, and more particularly to apparatus for detecting when a supply of article binder thread is substantially depleted, or when the continuity of the binder thread between a supply member and an article being bound has been interrupted, as a result of either a broken or a totally depleted binder thread. It is an object of this invention to provide new and improved apparatus of this character.

In the manufacture of communication cable, it is standard practice to gather insulated electrical conductor wires into groups and to .pass each group of wires through a binding head which wraps a binder thread, filament, ribbon or similar type material helically around the wires to bind them into a uni-t. The units. of bound wires then are gathered together to form a cable core and are passed through a binding head which wraps a binder thread or similar type material helically around the units to bind them together. The bound cable core then proceeds from the latter binding head to a takeup mechanism including a spool which i rotated about its longitudinal axis to wind the core thereon and which at the same time is rotated about its transverse axis to provide a twist to the core.

When the supply of binder thread material in one of the binding heads for a group of wires becomes depleted or the binder thread breaks, if the apparatus is not stopped immediately an extensive portion of the wires may pass through the binding head without being bound. If this unbound portion falls in a place where the completed cable subsequently is cut to produce a cable of a certain length, this part of the cable must be scrapped, thus resulting in a length of cable which may be too short.

Similarly, when the supply of binder thread in the binding head for the cable core becomes depleted or the binder thread breaks, if the apparatus is not stopped immediately :an extensive portion of the cable core may pass through the binding head without being bound. This unbound portion of the cable core then must be bound by hand. In the event that an unbound portion of. the cable core ha-swound onto the takeup spool before the apparatus is stopped, it is necessary to rewind the spool after it is filled and to bind the unbound portion of the cable core, before the core can be subjected to subsequent manufacturing operations. In each of these instances, the procedure involved is relatively expensive and time consuming.

Accordingly, another object of this invention is to provide new and improved apparatus for detecting when the supply of binder thread in a binding head is substantially depleted, and for stopping the binding head and cable making equipment associated with the binding head when this condition occurs. A further object of this invention is to provide new and improved apparatus for detecting when the continuity of the binder thread between a supply member and wires being bound by a speed between the members.

3,282,037 Patented Nov. 1, 1966 binding head has been interrupted, and for stopping the binding head and cable making equipment associated with the binding head when this condition occurs.

Another object of this invention is to provide new and improved apparatus for detecting when a supply of a binder thread is substantially depleted.

A further object of this invention is to provide new and improved apparatu for use with apparatus for wrapping a binder thread about an article, which is designed to detect when the supply of the binder thread is substantially depleted, and which includes a mechanism for compensating for factors which vary from one article wrapping operation to another.

A still further object of this invention is to provide new and improved apparatus for detecting when the continuity of a binder thread between a supply member and an article being bound has been interrupted.

A preferred embodiment of the invention is designed for use in apparatus including a binding head for wrapping a binder thread about an elongated article, such as a plurality of wires forming a cable core or a part thereof. The binding head includes a rotatable member for holding a supply of the binder thread and a rotatable member for Wrapping the binder thread about the article. The members are rotatable relative to one another during a wrapping operation and are arranged so that they stop rotating relative to one another if the continuity of the binder threzad between the supply member and the article is interrupted. Further, the rotational speed diiterential.

between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the binder thread.

In accordance with the invention, a pulse generator is mounted in part for rotation with the wrapping member and in part for rotation with the supply member so that as the members rotate relative to one another the pulse generator generates pulses at a frequency indicative of the rotational speed differential between the members. The pulse frequency is used to opeerate a mechanism for detecting when the supply of the binder thread is substantially depleted and/or for detecting when the continuity of the binder thread between the supply member and the article has been interrupted, as a result of either a broken or a totally depleted binder thread.

More specifically, the pulse generator includes an electrical pickup mechanism on one of the members and circumferentially and equally spaced ferromagnetic elements on the other of the members. As the binder thread is being wrapped about the article the members rotate relative to one another and the ferromagnetic elements move relative to the electrical pickup mechanism in close proximity thereto, to generate electrical pulses therein at a frequency indicative of the difference in rotational The pulses are transmitted from the electrical pickup mechanism to a mechanism which converts the pulses to :a direct current voltage having a magnitude indicative of the speed differential between the members.

This direct current voltage operates a sensing mechanism which stops the apparatus and/ or which operates a suitable alarm device as the binder thread supply member becomes substantially empty of the binder thread, or if the binder thread breaks. Further, in the event that the part of the sensing mechanism which is designed to operate as the supply member becomes substantially empty of the binder thread should malfunction, the part of the arbor at its left-hand end, as viewed in FIG. 1.

sensing mechanism which is designed to operate when the binder thread breaks also is designed to operate to stop the apparatus and/or to actuate an associated alarm device when the supply member does run empty of the binder thread. The sensing mechanism also includes an adjustable potentiometer mechanism for compensating for factors which may vary from one article wrapping operation to another.

This invention, together with further objects and advantages thereof, will best be understood with reference to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is an isometric view of a cable core binding head illustrating one application of the invention;

FIG. 2 is a partial cross-sectional view taken substantially along the line 22 of FIG. 1;

FIG. 3 is a partial cross-sectional View taken substantially along the line 33 of FIG. 2; and

FIG. 4 is an-electrical circuit further illustrating the application of the invention illustrated in FIGS. 1-3.

Referring to FIGS. 1-3 of the drawings, it is seen that the illustrated embodiment of the invention isshown in combination with a cable core binding head of a stranding cabler, which includes a rotatable arbor for supporting a supply of the binder thread material 11, and a rotatable shell member 12 for wrapping the binder thread material about a cable core 13. The illustrated embodiment of the invention is designed to stop the stranding cabler apparatus and to operate an alarm device when the supply of the binder thread material 11 is substantially depleted, or when the binder thread material breaks, or when the binder thread becomes totally depleted, in the event of a malfunction of the mechanism which is designed to operate when the binder thread is substantially depleted.

Referring to FIGS. 1 and 2, it is seen that the cable core 13 is made up of a plurality of groups of insulated Y electrical conductor wires 14, each group of wires having been bound with a binder thread 16 into a unit by a binding head (not shown) similar to the cable core binding head shown in the drawings, and the bound wire units then having been gathered together by a mechanism (noot shown) to form the cable core. As is best shown in FIGS. 1 and 2, the gathered bound wire units 14 enter the cable core binding head at one end, pass axially therethrough, and exit from the binding head at its other end. As the units 14 pass .from the binding head the binder thread 11 feeds from a cop or spool assembly 17 on which it is wound and which is mounted on the rotatable arbor 10, and the thread is wrapped around the units by the rotating shell member 12, in a manner described in greater detail hereinbelow. The bound units then proceed from the binding head to a suitable takeup mecha-- nism (not shown) of the stranding cabler apparatus.

As is best shown in FIGS. 1 and 3, the cop assembly 17 is of a split-type construction and includes a pair of substantially half cylinder members 18. Each half cylinder member 18 includes a pair of longitudinally extending tongues 19 which project radially inward in opposed relationship. When the cop assembly 17 is positioned on the arbor 10 the tongues 19 are received in associated longitudinally extending grooves 21 in the arbor 10, and corresponding ones of the tongues mate with one another as shown in FIG. 3. The cop assembly 17 is positioned on the arbor 10, and is removed from the arbor, by sliding the cop assembly axially on and off the During the binding operation, centrifugal force produced by the rotation of the arbor 10 causes the tongues 19 of the half cylinder members 18 to bear against opposed side walls of the grooves 21 in the arbor such that the cop assembly 17 is held against axial movement off the arbor by the friction produced between the tongues and the groove side walls.

Referring to FIGS. 1 and 2, it is seen that the shell member 12 for wrapping the binder thread 11 about the units of bound wires 14 is a sleeve-like cylindrical member having an opening 22 formed therethrough. As is best shown in FIG. 1, during the binding operation the binder thread 11 is received in one or the other of two slots 23 at opposite ends of one edge of the opening 22, the slot in which the binder thread is received being dependent upon the direction'in which the shell member 12 is rotating. As is best shown in FIG. 2, the shell member 12 is fixedly mounted on an annular housing 24 which is suitably secured, such as by screws 26, to a hollow shaft 27 through which the cable core 13 passes axially during the binding thereof. The hollow shaft 27 is mounted for rotation by suitable bearings in the upper portion of a standard 28 suitably secured at its lower end to a base member 29. The shell member 12, the annular housing 24 and the hollow shaft 27 are driven clockwise, as viewed in FIG. 1, by a drive mechanism 31 connected to the hollow shaft and including a direct current motor 32 mounted on the base member 29.

The binder thread supply support arbor 10 is journalled for rotation by suitable bearings on the hollow shaft 27 and includes an annual flange33 at its left-hand end, as viewed, in FIG. 2, which is-engaged with a plurality of friction studs 34 screw threaded into the annular housing 24. Thus, as the shell member 12, the annular housing 24 and the hollow shaft 27 are rotated clockwise in FIG. 1 by the drive mechanism 31 so that the shell member 12 wraps the binder thread 11 around the cable core 13, the friction studs 34 acting against annular flange 33 tend to rotate the arbor 10 and the cop assembly 17 therewith. However, referring to FIG. 1, it is seen that as the shell member 12 is rotating clockwise to wrap the binder thread 11 around the cable core 13, the binder thread retards the rotation of the arbor 10 and the cop assembly 17 so that they lag behind the shell member 12 and pay off the required amount of binder thread from the cop assembly. This lag of the arbor 10 and the cop assembly 17 with respect to the shell member12, and thus the speed differential between them and the shell member, progressively increases as the circumference of the binder thread 11 on the cop assembly decreases.

Further in this regard, as the binder thread 11 on the cop assembly 17 becomes substantially depleted during a binding operation, this speed differential reaches a certain value, the magnitude of which varies depending upon the speed of the cable core 13 through the binding head, the diameter or circumference of the cable core, the length of lay of the binder thread 11 on the cable core, and the circumference or diameter of the cop assembly 17. In addition, if the binder thread 11 breaks during a binding operation, or becomes totally depleted, so that it no longer retards rotation of the arbor 10 and the cop assembly 17, the friction studs 34 will cause the arbor 'and the cop assembly to rotate with the shell member 12 at the same speed as the shell member, and the speed differential between them and the shell member will drop to zero. When one of these conditions occurs, the illustrated embodiment of the invention, now to be described, is designed to respond to the condition which has occured, to stop the cable stranding apparatus and to operate an alarm device.

Referring to FIGS. 2 and 3, it is seen that in accordance with this invention a pulse generator 36, including an hand end (FIG. 2) to the housing. At its left-hand end, as viewed in FIG. 2, the electrical pickup unit 37 is 10-' cated in an aperture through an annular ring member 41 of a suitable insulating material, such as plastic, which encircles the annular housing 24 and which is secured thereto by screws 42, one of which is shown at the top center of FIG. 2. The electrical pickup unit 37 may be of any suitable type which includes a coil and a magnetic core, and which is designed so that when a ferromagnetic member cuts the flux of the magnetic core a pulse is induced in the coil.

The annular toothed wheel 38 may be of any suitable ferromagnetic material, such as steel, and is secured by bolts 43 to the periphery of the annular flange 33 of the arbor 19. The wheel includes circumferentially and equally spaced teeth 44 (FIG. 3) about its periphery arranged to move adjacent the electrical pickup unit 37 and to cut the magnetic field thereof sequentially as the arbor and the shell member 12 rotate relative to one another, as described hereinabove, thereby inducing pulses 45 (FIG. 4) in the coil of the electrical pickup unit at a frequency representative of the speed differential between the shell member and the arbor.

The pulses 45 in the coil of the electrical pickup unit 37 are transmitted to a speed sensing circuit 46 shown in FIG. 4, by conductors 47 (FIG. 2, lower center) connecting the coil to a pair of annular slip rings 48 and 49, and by carbon brushes 51 (FIGS. 1 and 3) engaged with the slip rings and connected to the speed sensing circuit by conductors 52. The slip rings 48 and 49 are force fitted or otherwise suitably secured to the periphery of the insulator ring member 41 and may be of any suitable electrically conducting material, such as brass. The brushes 51 are mounted in suitable housings 53 and are biased into engagement with the slip rings 48 and 49 by springs within the housings. The housings 53 are secured to brackets 54 fixedly mounted on a bearing retaining ring 56 (FIGS. 1 and 2) secured to the standard 28. The conductor 47 connecting the coil of the electrical pickup unit 37 to the slip ring 49 extends thereto through a tubular passage 57 (FIG. 2) drilled or otherwise suitably formed in the insulator ring member 41 so that as the ring member 41 rotates with the annular housing 24 during a binding operation, the conductor will not interfere with the brush 51 which is engaging the slip ring 48.

As the cop assembly 17 becomes substantially empty of the binder thread 11 during a binding operation, the speed sensing circuit 46 (FIG. 4), in response to the pulse frequency being produced by the pulse generator 36, operates a relay 58 in the operating circuit of the stranding cabler apparatus to open a contact 59, thereby stopping the apparatus. The relay 58 also operates a contact 61 in an indicating circuit to energize a suitable alarm device 62. For this purpose, the speed sensing circuit 46 includes a voltage sensitive relay 63, which, when a preselected voltage is impressed thereon, is designed to conduct and to operate the relay 58. The voltage sensitive relay 63 may be of any suitable type, as for example, a relay designed to close a contact 64 thereof when a preselected voltage is applied to the relay, a thyratron tube, or a similar type device.

Voltage for operating the voltage sensitive relay 63 is provided in the sensing circuit 46 by a suitable converter 66 which is designed to receive the pulses 45 produced by the pulse generator 36 and to convert the pulses to a direct current voltage representative of the speed differential between the binder thread support arbor 10 and the shell member 12. A portion of this direct current voltage then is tapped off by a potentiometer 67 such that when the cop assembly 17 is running substantially empty of the binder thread 11, the voltage being impressed on the voltage sensitive relay 63 is equal to the operating voltage of the relay.

Preferably, the potentiometer 67 is calibrated in units of speed differential between the arbor 10 and the shell member 12 since, as noted hereinabove, the magnitude of this speed differential as the cop assembly 17 on the arbor 10 is running substantially empty of the binder thread 11 is a function of the different variables in the binding process, namely, the speed of the cable core 13 through the binding head, the diameter of the cable core, the length of lay of the binder thread 11 on the cable core, and the diameter of the cop assembly 17. Further, since the speed of the cable core 13 through-the binding head may vary slightly during a binding operation, the potentiometer 67 may be controlled in a suitable manner so that the setting thereof is varied automatically in response to changes in cable core speed, if so desired. In addition, the potentiometer 67 could be replaced by a plurality of potentiometers, or similar type devices, each suitably calibrated in terms of one of the above-mentioned variable factors in the binding process.

The calibration of the potentiometer 67 in units of speed differential between the arbor 10 and the shell member 12 may be accomplished in various manners. By way of illustration, the arbon 10 can be held stationary while the shell member 12 is rotated relative to the arbor at different speeds by the drive mechanism 31. The resistance setting on the potentiometer 67 for each speed then can be determined by measuring the voltage at the input to the voltage sensitive relay 63, and by observing and marking the resistance setting of the potentiometer which provides a voltage at the relay input equal to the operating voltage of the relay.

The proper speed differential setting of the calibrated potentiometer 67 for a particular binding operation can be determined in a conventional manner, as for example, by the formula R=S F/C, where R is the speed differential between the arbor 1t) and the shell member 12 in revolutions per minute, S is the speed of the cable core 13 in feet per minute, F is the footage of the binder thread 11 required per foot of cable core, and C is the circumference of the cop assembly 17 in feet. In using this formula the value of F, the footage of the binder thread 11 required per foot of cable core, is a function of the diameter of the cable core 13 and the length of lay of the binder thread 11 on the cable core, and can be determined in any suitable manner, as for example by computation, or by actual measurement.

The part of the speed sensing circuit 46 for detecting a break in the binder thread material 11 includes a meter relay 68 of a suitable type having a normally open contact 69. When the stranding cabler, including the binding head, is operating such that the arbor 10 and the shell member 12 are rotating relative to one another and a direct current voltage is being produced by the converter 66, the direct current voltage operates the meter relay 68 to maintain its normally open contact 69 closed, thereby energizing a run relay 71 which forms a part of the normal operating circuit of the stranding cabler apparatus, and which maintains a contact 72 closed so that the apparatus keeps operating.

If the binder thread 11 breaks, however, the friction studs 34 cause the arbor 10 and the shell member 12 to begin rotating as a unit, and the pulse generator 36, comprised of the electrical pickup unit 37 and the pulse wheel 38, stops generating the pulses 45. The direct current voltage output of the converter 66 in the speed sensing circuit 46 then drops to zero and the meter relay 68 is de-energized so that its contact 69 opens to de-energize the run relay 71. This allows the contact 72 to open to stop the cable stranding apparatus, including the binding head motor 32, and allows a contact 73 in an indicating circuit, which is held open by the run relay 71, to close to energize a suitable alarm device 74.

The meter relay 68 also operates in the capacity of a depleted binder thread detecting mechanism, in the event that the above described mechanism for detecting when the binder thread 11 is substantially depleted, comprising the voltage sensitive relay 63 and the potentiometer 67, should malfunction. In this regard, if the mechanism 63, 67 does not operate to stop the cabler apparatus, as

7 the cop assembly 17 subsequently runs empty of th binder thread 11, the friction studs 34, as in the case of a broken binder thread 11, cause the arbor 10 and the shell member 12 to begin rotating in unison. The pulse generator 36 then ceases to produce the pulses 45 and the direct current voltage in the speed sensing circuit 46 drops to zero. This de-energizes the relay 68, and its contact 69 opens to de-energize the run relay 71, thereby permitting the contact 72 to open to stop the apparatus, and permitting the contact 73 to close to operate the alanm device '74.

Referring to FIG. 4, it is seen that when the operation of the stranding cabler is started, as for example by the closing of a switch 76, the meter relay contact 69 is open and cannot complete a circuit to energize the run relay 71 to close the contact '72. Accordingly, a plugging switch 77 of a suitable type and having a normally closed contact 78 is provided in series with the run relay 71 and a supply source 79 for the stranding cabler, to bypass the meter relay contact 69 during the initial operating phase of the cabler. The plugging switch 77 is mounted on the base member 29 by a suitable bracket, as shown in FIG. 1, and is driven by the binding head motor 32.

Further, the plugging switch 77 is adjusted so that its contact 78 opens when the cable core speed throughthe binding head has reached a preselected value, as for example, feet per minute. By this time the meter relay contact 69 will have closed so that it then maintains the run relay 71 energized to keep the machine operating until the binder thread 11 breaks, or the cop assembly 17 runs out of the binder thread, as above described.

In certain instances it is desirable to determine the speed differential between the arbor 10 and the shell member 12 at a particular instant, and accordingly a voltmeter 81 (FIG. 4) of a suitable type is provided in the sensing circuit 46 for measuring the voltage output of,

the converter 66. The voltmeter 81 may be calibrated in units of speed differential between the arbor 10 and the shell member 12, if so desired.

In operation, as the binder thread 11 is being wrapped about the cable core 13, the arbor 10, and the cop assembly 17 and the pulse wheel 38 thereon, are rotated relative to the annular housing 24, the shell member 12 and the electrical pickup unit 37 thereon, by the retarding action of the binder thread. As a result of this relative movement, the circumferentially and equally spaced teeth 44 on the pulse wheel 38 induce the pulses 45 (FIG. 4) in the electrical pickup unit 37 at a frequency representative of the speed differential between the arbor 10 and the shell member 12. The pulses 45 are transmitted through the conductors 47, the slip rings 48 and 49, the brushes stantially empty condition, the voltage sensitive relay 63 operates to close the contact 64, thereby energizing the relay 58 to open the contact 59 to stop the stranding cabler apparatus, including the binder head motor 32, and to close the contact 61 to operate the alarm device 62.

When the switch 76 is closed to start the stranding cabler apparatus, the normally closed contact 78 of the plugging switch 77 completes a circuit to energize the run relay 71, which closes the contact 72 so that the machine will begin to operate. Subsequently, the direct current voltage output of the converter 66 in the speed sensing circuit 46, as a result of the operation of the pulse generator 36, energizes the meter relay 68 to close its normally open contact 69. Thus, when the plugging switch contact 78 subsequently opens, the meter relay contact 69 maintains the run relay 71 energized to keep the machine operating. If the binder thread 11 breaks, however, so that the pulse generator 36 stops producing the pulses 45, the direct current voltage in the speed sensing circuit 46 drops to zero and the meter relay 68 becomes de-energized so that its contact 69 opens to de-energize the run relay 71, thereby permitting the contact 7 2 to open to stop the machine, and thereby permitting the contact 73 to close to operate the alarm device 74.

In the event that the mechanism for detecting when the cop assembly 17 is running substantially out of the binder thread 11, including the voltage sensitive relay 63 and the potentiometer 67, does not operate to stop the stranding cabler apparatus, when the cop assembly 17 subsequently does run out of the binder thread the meter relay 68 will operate to stop the apparatus and to operate the alarm device 74 in the same manner as described hereinabove for a broken binder thread.

While one embodiment of the invention has been disclosed many modifications will be apparent and it is intended that the invention be interpreted as including all modifications which fall within the true spirit and scope of the invention. i

What is claimed is:

1. In combination with apparatus including a rotatable member for wrapping a thread about an article and a rotatable member for holding a supply of the thread, wherein the members rotate relative to one another during a wrapping operation and wherein the rotational speed differential between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the thread, mechanism which comprises:

a pulse generatormounted in part for rotation with the wrapping member and in part for rotation with the supply member so as to generate pulses at a frequency indicative of the speed differential between the members; and

sensing means responsive to the pulse frequency and being operable when the pulse frequency being generated is indicative of the predetermined value of the speed differential between the members.

2. In combination with apparatus including a rotatable member forwrapping a thread about an article and a rotatable member for holding a supply of of the thread, wherein the members rotate relative to one another during a wrapping operation and wherein the rotational speed differential between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the thread, mechanism which comprises:

a pulse generator mounted in part for rotation with the wrapping member and in part for rotation with the supply member so as to generate pulses at a frequency indicative of the speed differential between the members; and sensing means responsive to the pulse frequency and being operable when the pulse frequency being generated is indicative of the predetermined value of of the speed differential between the members, said sensing means including potentiometer means adjustable to compensate for factors which may vary from one article wrapping operation to another. 3. In combination with apparatus including a rotatable member for wrapping a thread about an article and a rotatable member for holding a supply of the thread,

wherein the members rotate relative to one another during a wrapping operation and stop rotating relative to one another if the continuity of the thread between the supply.

9 comes substantially empty of the thread, mechanism which comprises:

a pulse generator mounted in part for rotation with the wrapping member and in part for rotation with the supply member so as to generate pulses at a frequency indicative of the speed differential between the members, said pulse generator being arranged so as to generate no pulses when the members are not rotating relative to one another;

first sensing means responsive to the pulse frequency and being operable when the pulse frequency being generated is indicative of the predetermined value of the speed differential between the members; and

second sensing means responsive to the condition in which no pulses are being generated by said pulse generator.

4. In combination with apparatus including a rotatable member for wrapping a thread about an article and a rotatable member for holding a supply of the thread, wherein the members rotate relative to one another during a wrapping operation and stop rotating relative to one another if the continuity of the thread between the supply member and the article is interrupted, and wherein the rotational speed differential between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the thread, mechanism which comprises:

electrical pickup means on one of the members;

circumferentially and equally spaced ferromagnetic means on the other of the members movable relative to said electrical pickup means in close proximity thereto during relative rotation of the members, for generating electrical pulses in said electrical pickup means at a frequency indicative of the speed differential between the members, said ferromagnetic means being arranged so as to generate no pulses in said electrical pickup means when the members are not rotating relative to one another;

first sensing means responsive to the pulse frequency and being operable when ,the pulse frequency being generated is indicative of the predetermined value of the speed differential between the members; and

second sensing means responsive to the condition in which no pulses are being generated in said electrical pickup means by said ferromagnetic means.

5. In combination with apparatus including a rotatable member for wrapping a thread about an article and a rotatable member for holding a supply of the thread, wherein the members rotate relative to one another during a wrapping operation and stop rotating relative to one another if the continuity of the thread between the supply member and the article is interrupted, and wherein the rotational speed differential between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the thread, mechanism which comprises:

a pulse generator mounted in part for rotation with the wrapping member and in part for rotation with the supply member so as to generate pulses at a frequency indicative of the speed differential between the members, said pulse generator being arranged so as to generate no pulses when the members are not rotating relative to one another;

means for converting the pulses to a direct current voltage having a magnitude indicative of the speed differential between the members;

first sensing means responsive to the direct current voltage and being operable when the direct current voltage being produced is indicative of the predetermined value of the speed differential between the members; and

second sensing means connected to said pulseconverting means and being responsive to the condition in which no pulses are being generated by said pulse generator whereby no direct current voltage is being produced by said pulse converting means.

6. In combination with apparatus including a rotatable member for wrapping a thread about an article and a rotatable member for holding a supply of the thread, wherein the members rotate relative to one another during a wrapping operation and stop rotating relative to one another if the continuity of the thread between the supply member and the article is interrupted, and wherein the rotational speed differential between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the thread, mechanism which comprises:

a pulse generator mounted in part for rotation with the wrapping member and in part for rotation with the supply member so as 'to generate pulses at a frequency indicative of the speed differential between the members, said pulse generator being arranged so as to generate no pulses when the members are not rotating relative to one another;

first sensing means for stopping the apparatus when the thread supply member becomes substantially empty of the thread, said first sensing means being responsive to the pulse frequency and being operable when the pulse frequency being generated is indicative of the predetermined value of the speed differential between the members; and

second sensing means responsive to the condition in which no pulses are being generated by said pulse generator and being operable to stop the apparatus if the thread breaks, said second sensing means also being operable to stop the apparatus if the supply member runs empty of the thread, in the event that said first sensing means fails to stop the apparatus when the supply member becomes substantially empty of the thread.

7. In combination with cable making apparatus having a binding head which includes a rotatable member for wrapping a binder thread about a plurality of wires and a rotatable member for holding a supply of the binder thread, wherein the members rotate relative to one another during a wrapping operation and stop rotating relative to one another if the continuity of the binder thread between the supply member and the wires is interrupted, and wherein the rotational speed differential between the members progressively changes during a wrapping operation and reaches a predetermined value as the supply member becomes substantially empty of the binder thread, mechanism which comprises:

a pulse generator mounted in part for rotation with the wrapping member and in part for rotation with the supply member so as to generate pulses at a frequency indicative of the speed differential between the members, said pulse generator being arranged so as to generate no pulses when the members are not rotating relative to one another;

means for converting the pulses to a direct current voltage having amagnitude indicative of the speed differential between the members;

first sensing means for stopping the cable making apparatus, including the binding head, when the thread supply member becomes substantially empty of the binder thread, said first sensing means being responsive to the direct current voltage and being operable when the direct current voltage being produced is indicative of the predetermined value of the speed differential between the members, and said first sensing means including potentiometer means adjustable to compensate for factors which may vary from one wire wrapping operation to another; and

second sensing means connected to said pulse converting means and being responsive to the condition in which no pulses are being generated by said pulse 3,282,037 1 1 1 2 generator whereby no direct current voltage is being References Cited by the Examiner produced by said pulse converting means, said sec- UNITED STATES PATENTS 0nd sensing means being operable to stop the cable making apparatus, including the binding head, if 216951376 11/1954 Emms et a1 324-40 the binder thread breaks or if the supply member 5 3,086,157 4/1963 Branco 318328 runs empty of the binder thread as a result of said 3 15 115 11 19 4 Adelmann first sensing means, failing to stop the cable making apparatus, including the binding head, when the WALTER L CARLSON, Primary Examiner M. I. LYNcH Assistant Examiner.

supply member becomes substantially empty of the binder thread. 

1. IN COMBINATION WITH APPARATUS INCLUDING A ROTATABLE MEMBER FOR WRAPPING A THREAD ABOUT AN ARTICLE AND A ROTATABLE MEMBER FOR HOLDING A SUPPLY OF THE THREAD, WHEREIN THE MEMBERS ROTATE RELATIVE TO ONE ANOTHER DURING A WRAPPING OPERATION AND WHEREIN THE ROTATIONAL SPEED DIFFERENTIAL BETWEEN THE MEMBERS PROGRESSIVELY CHANGES DURING A WRAPPING OPERATION AND REACHES A PREDETERMINED VALUE AS THE SUPPLY MEMBER BECOMES SUBSTANTIALLY EMPTY OF THE THREAD, MECHANISM WHICH COMPRISES: A PULSE GENERATOR MOUNTED IN PART FOR ROTATION WITH THE WRAPPING MEMBER AND IN PART FOR ROTATION WITH THE SUPPLY MEMBER SO AS TO GENERATE PULSES AT A FREQUENCY INDICATIVE OF THE SPEED DIFFERENTIAL BETWEEN THE MEMBERS; AND SENSING MEANS RESPONSIVE TO THE PULSE FREQUENCY AND BEING OPERABLE WHEN THE PULSE FREQUENCY BEING GENERATED IS INDICATIVE TO THE PREDETERMINED VALUE OF THE SPEED DIFFERENTIAL BETWEEN THE MEMBERS. 